Onset of activity of fluralaner (BRAVECTO¿) against Ctenocephalides felis on dogs

Janina Taenzler,Christina Wengenmayer,Josephus Fourie,Eva Zschiesche,Heike Williams,Rainer Roepke,Anja R Heckeroth

doi:10.1186/preaccept-1563099569137345

Abstract

BackgroundFluralaner (Bravecto™) is a novel systemic insecticide and acaricide that provides long persistent antiparasitic activity following a single administration at the minimum dose of 25 mg/kg body weight.MethodsThree negative controlled, randomized studies were conducted in dogs to evaluate the start to kill (1 study) and the speed of flea kill (2 studies) of fluralaner. All dogs were infested prior to treatment with unfed adult C. felis fleas. Dogs in the treated groups were administered once orally with fluralaner at a minimum dose of 25 mg/kg body weight, while dogs in the control groups were not treated. Separate control and treatment groups were paired at each time point of flea assessment. Flea counts were performed by combing dogs at either 0.5, 1, 2, or 4 hours after fluralaner treatment to measure the start to kill. To evaluate the speed of flea kill over 12 weeks, flea counts were performed by combing dogs at either 4, 8, 12, or 24 hours after fluralaner treatment and then at 4, 8, 12, or 24 hours after each flea re-infestations performed at 4, 8, and 12 weeks following treatment.ResultsIn the start to kill study, the fluralaner activity against fleas started already at 1 hour post-treatment (8% numerical efficacy). At 2 and 4 hours post-treatment, the flea reduction was significant with 36.7% and 88% efficacy, respectively.In the speed of kill studies, the efficacy against fleas after fluralaner treatment was 80.5% at 4 hours and remained ≥ 99.4% at 8, 12 and 24 hours. After flea re-infestations in weeks 4, 8 and 12, the efficacy at 4 hours was 96.8, 91.4, and 33.5%, respectively. Efficacy at 8, 12 and 24 hours after flea re-infestations was 98.0-100% for the 12 weeks of the study. Except for 4 hours after the 12-week flea re-infestation, flea reduction was significant for all time points after flea re-infestation.ConclusionsSingle oral fluralaner administration rapidly eliminates existing flea infestations and provides excellent protection against fleas over 12 weeks following treatment.

Highlights

Fluralaner (BravectoTM) is a novel systemic insecticide and acaricide that provides long persistent antiparasitic activity following a single administration at the minimum dose of 25 mg/kg body weight
No adverse event considered to be related to oral fluralaner treatment was observed in any dog
A few or no fleas were observed on the dogs at these time points

Summary

Introduction

Fluralaner (BravectoTM) is a novel systemic insecticide and acaricide that provides long persistent antiparasitic activity following a single administration at the minimum dose of 25 mg/kg body weight. The active ingredient of BravectoTM, fluralaner, is a member of the isoxazoline class, a novel class of antiparasitic drugs that inhibits γ-aminobutyric acid (GABA)and glutamate-gated chloride channels with significant selectivity for insect neurons over mammalian neurons [5,6]. Fluralaner formulated as a flavoured chewable tablet is commercially available for immediate and persistent killing of ticks and fleas on dogs over 12 weeks, eliciting its primary action through feeding activity [7]. A single dose of fluralaner provided 12 weeks activity against fleas in dogs [8], and it was shown to be safe and well tolerated [8,9]

Methods

Results

Discussion

Conclusion